Radio communication systems typically use a receiver (e.g., a selective call receiver or "pager") that has at least one unique call address. These radios receive and decode an address, then typically alert the user to the presence of incoming information and operate to present this information. Radio communication systems are an excellent vehicle for delivering voice, numeric, alphanumeric or coded information to a user.
Most contemporary selective call radio receivers employ a crystal controlled single frequency oscillator as a conversion signal source. Some contemporary "high-end" selective call radio receivers use a crystal controlled, microcontroller programmed frequency synthesizer as a conversion signal source. These high-end receivers allow for a more flexible environment in manufacturing and distributing dissimilar frequency models of a selective call radio receiver because a manufacturer needs to stock only one or two master frequency crystals. This scenario is not without its problems, as each microcontroller and its accompanying frequency synthesizer must be programmed by the manufacturer for proper operation. If a user desires to use their selective call radio receiver in a number of regions across a geographic area, the receiver must be frequency agile, that is, capable of changing its receive channel frequency. This is necessary because typically, Radio Common Carriers cannot always arrange for like channel frequencies across a wide geographic area.
Attempts have been made to solve the preceding problem by adding pre-programmed frequency selection to conventional two-way radios via direct channel entry selection (e.g., entering a frequency) and "alias" channel selection (e.g., Channel A corresponds to 152.48 MHz, Channel B corresponds to 161.5 MHz, etc.). All of these methods require a user to have intimate knowledge of the system that their receiver is operating in to select the correct channel for reception. This drawback cannot be overcome without completely redesigning the operating systems to accommodate automatic frequency selection and direction such as in a conventional cellular telephone system.
Consequently, what is needed is a simplistic method and apparatus that allows a user to easily select a correct operating channel frequency when operating their selective call radio receiver in a plurality of geographical areas.